Yes, you can safely use LMDE 2. It is based on Debian Jessie. It receives security updates till end of May 2018 from the Debian Security Team and from June 2018 till end of May 2020 from the Debian Long-Term Support (LTS) team.

LMDE 2 comes with the 3.16 kernel, which is still being supported in Debian. It works quite well, but if you need a newer kernel you can add the Debian backports and install the kernel from there (currently, I believe the backported kernel is version 4.9).

will also be included in the Debian Defaulth service of error and Timeshift reports???

I don't know about that.

Cheers!

"Once you can accept the universe as matter expanding into nothing that is something, wearing stripes with plaid comes easy."
- Albert Einstein